U.S. Pat. No. 4,398,939, issued Aug. 16, 1983 to Levitt, discloses herbicidal thiophenesulfonylureas such as ##STR1##
European Patent Application No. 30,142, published June 10, 1981, discloses herbicidal thiophene sulfonylureas such as ##STR2##
U.S. Pat. No. 4,378,991, issued Apr. 5, 1983 discloses o-phenyl sulfonylureas such as ##STR3##
European Patent Application No. 83,975, published July 20, 1983, and European Patent Application No. 85,476, published Aug. 10, 1983, disclose herbicidal benzenesulfonamides of the formula ##STR4## where Q is various 5- and 6-membered, saturated, unsaturated or partially unsaturated heterocyclic rings.
South African Patent Application No. 83/8416 (published May 12, 1984) discloses herbicidal sulfonamides of formula ##STR5## wherein A is an unsaturated or only partially saturated 5- or 6-membered heterocyclic ring system which is bonded through a carbon atom and contains 1, 2 or 3 heteroatoms and which may be substituted by C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 haloalkyl, C.sub.1 -C.sub.4 alkoxy, C.sub.1 -C.sub.4 alkylthio, C.sub.2 -C.sub.8 alkoxyalkyl, di(C.sub.1 -C.sub.4 alkyl)amino, halogen, cyano or nitro.